Irish Rail has announced its banning alcohol on a number of its Friday services.
It follows complaints over anti-social behaviour.
The four services affected are the 11:25hrs Heuston-Galway route; 13:25hrs Heuston-Galway; 15:35hrs Heuston-Galway; and the 14:45hrs Heuston-Westport.
The ban comes into effect from next Friday (October 12th).
No alcohol will be sold on board the trains, while anyone boarding with alcohol will have it confiscated.
Details of the restrictions will be displayed at stations, and customers will also be advised of the ban when booking online.
The company says there has been "high volumes of complaints" across the services impacted.
Jane Creegan from Irish Rail explained: "The vast majority of people who want to enjoy a drink do so without making any impact on their fellow passengers.
"Unfortunately, we've had particularly large groups of people... they may be intimidating to other customers when they are drinking large amounts of alcohol, particularly people bringing on board large amounts of alcohol."
A half dozen other Friday and Sunday services - mostly between Waterford and Dublin - are already 'alcohol free'.